Nearly 50,000 tons of sludge at water treatment facilities has been found to contain radioactive cesium as the result of the accident at the Fukushima Daiichi nuclear power plant. Over 1,500 tons is so contaminated that it cannot be buried for disposal.

Water treatment facilities in eastern and northeastern Japan have been discovering sludge containing cesium.

The health ministry says there is 49,250 tons of such sludge in 14 prefectures in eastern and northeastern Japan.

A total of 1,557 tons in 5 prefectures, including Fukushima and Miyagi, was found to contain 8,000 or more becquerels per kilogram. This sludge is too radioactive to be buried for disposal.

The most contaminated sludge, with 89,697 becquerels per kilogram, was discovered at a water treatment facility in Koriyama City, Fukushima.

The ministry says 76 percent of the roughly 50,000 tons of radioactive sludge is being stored at water treatment plants and they have no ways to dispose of most of it.

It says more than 54,000 tons of additional sludge has not been checked for radioactive materials.

The ministry plans to study how to dispose of the radioactive sludge.

“The health ministry will cooperate with the Ministry of Land, Infrastructure, Transport and Tourism and consider reprocessing the sludge as soil for GARDENING.”

Over 1,500 metric tons of radioactive sludge requiring controlled handling has been found in five prefectures across Japan amid the ongoing Fukushima nuclear crisis, the government announced on July 28.

The Ministry of Health, Labor and Welfare said that an examination of 49,250 tons of sludge produced during decontamination work at water-treatment facilities in Tokyo and 13 other prefectures by July 12 detected 1,557 tons of sludge in five prefectures with a level of radioactivity of over 8,000 becquerels per kilogram. It has judged that sludge with radioactivity of over 8,000 becquerels per kilograms should be placed temporarily at controlled disposal facilities.

The five prefectures are Fukushima, Miyagi, Niigata, Tochigi and Gunma.

The survey also found that 36,333 tons of sludge is being stored on the grounds of water treatment facilities without any decision made on what to do with it.

The survey did not find any cesium-contaminated sludge with radioactivity exceeding 100,000 becquerels per kilogram, a level at which storage in a sealed facility is recommended. However, 33,950 tons of sludge with radioactivity exceeding 100 becquerels per kilogram but below 8,000 becquerels per kilogram, which cannot be buried in places where homes will be built, was found in 11 prefectures, including Tokyo and Saitama.

The most radioactive sludge was found in Koriyama, Fukushima Prefecture, where a level of 89,697 becquerels was detected.

A total of 54,613 tons of untested sludge remains in the 14 prefectures. Problems have emerged over how to treat the sludge and where to keep it.

Health ministry officials say that final disposal sites have often been reluctant to accept sludge contaminated with radioactive materials, and many sewage facility operators have stored the sludge on their premises. Tokyo has already buried all 6,912 tons in landfill areas, but many local bodies are struggling to find storage sites.
The health ministry will cooperate with the Ministry of Land, Infrastructure, Transport and Tourism and consider reprocessing the sludge as soil for gardening.